Orthopaedic surgeons often face the problem where a fractured bone, which appeared completely healed in an X-ray examination, refractures during the normal activity of a patient. Ultrasonic methods of determining the degree of fracture healing have also been attempted without much success as a practical test. Therefore, there is an obvious need for a more reliable non-invasive method. This investigation will be an attempt to develop such a method utilizing the principle of reflection of stress waves at any structural defect, e.g., the site of a healing fracture. The healing bone will be subjected to a small impact and the characteristics of the reflected and transmitted wave pulse will be calibrated to indicate the state of healing as evaluated by clinical observation, histological and X-ray examination, and mechanical testing. It is expected that development of such a method will result in improved health care of patients with fractured bone or other bone lesions.